This invention relates to improvements in or relating to the magazine-type cigarette feeding apparatuses for a cigarette packaging machine.
One of the known systems in use for feeding cigarettes from the manufacturing machine or machines to the packaging machine uses substantially parallelepiped rechargeable magazines.
The feeding operation according to this conventional system comprises in practice the following four stages: the placing of the cigarettes in said magazines by filling devices disposed at the exit of the manufacturing machines, the feeding of the full magazines to their zone of utilization, their emptying into the feed hopper of the packaging machine, and finally the transfer of the empty magazines back to the filling devices.
The improvements according to the invention aim at avoiding the stoppage of the packaging machine should the main conveyor of the feeding apparatus not supply full cigarette magazines with the required rate.
Magazine-type cigarette feeding apparatuses are known, for example, from the U.S. Pat. Nos. 3,229,837 and 3,298,549, from the German Pat. Nos. 1.157.534, 1.173.831 and 1.176.555 as well from the U.S. Pat. Nos. 3,486,647 and 4,085,759 in the name of the Applicant thereof.
Said known devices substantially comprise (a) an intermittently moved main conveyor for feeding full cigarette magazines from a loading position, wherein said magazines are manually or automatically loaded into seats provided on said main conveyor, to a withdrawal position, (b) intermittently moved elevator means for elevating said magazines from said withdrawal position to a transfer position overlying said main conveyor, (c) transfer means for transferring the magazines from said transfer position to an overturning position and (d) overturning means for emptying the cigarettes contained in said magazines into said hopper.
In said known apparatuses, the feeding of the cigarettes to the hopper is monitored by means sensitive to the level of the mass of cigarettes in the hopper independently from the possible absence of magazines in one or more seats of the main conveyor: it follows that the correct operation of said known apparatuses, i.e. the condition to be fulfilled so that a full cigarette magazine becomes emptied into the hopper during each cycle at the rate required by the packaging machine, is that a full cigarette magazine is present at the final end, or withdrawal position, of the main conveyor after each of its stepwise advancements.
If this condition is not fulfilled, i.e. if even a single magazine is not present in the withdrawal position, the drawback occurs of being compelled to stop the packaging machine.
A further drawback of the conventional apparatuses resides in the necessity of continuously checking the correct arrangement or disposition of the magazines in the seats of the main conveyor.
Any attempt to overcome the drawback due to the absence of magazines by manually inserting magazines into the empty seats of the intermittent main conveyor does not necessarily ensure success, as it presupposes the continuous presence and constant attention of an operator.
As an alternative to this system, i.e. if the empty seats are filled automatically, more complex and costly equipment is necessary, provided with bulky magazine buffer stores, as described for example in the already mentioned U.S. Pat. No. 4,085,759.